Traditionally, fire fighting apparatus consisted of a flexible hose connected to a source of pressure fluid at one end and at the other end to a nozzle, wherein the flow of fluid could be shut off by a simple valve located at the nozzle. Recently, however, there has been a demand for a more easily operated valve located at the nozzle and this has been brought about by a change in the nature of fire fighting. For one thing, there has been a tendency to mount the nozzle on the upper part of a piece of mobile equipment and to make available to the fire fighter a number of fire extinguishing media. It is common practice, for instance, to supply to the nozzle water (on the one hand) and a gas-propelled powder (on the other hand). By providing the valving at the nozzle, it has been possible for the fire fighter to select the proper medium and to apply the fire extinguishing medium in short bursts, if necessary. Considerable power is required to operate simple valves and this is not only tiring, but also reduces the sensitivity of the control. Various means, of course, are available to operate simple valves, but, generally speaking, they require the use of either a lever which requires two hands for operation, or a lever arranged as a squeeze grip which can be tiring, as well as introducing delicate equipment into a less-than-ideal environment. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a fire fighting nozzle in which the opening and closing of the main fluid valve takes place under finger control.
Another object of this invention is the provision of a fire fighting nozzle whose main valve is operated by the fluid which it controls.
A further object of the present invention is the provision of a fire fighting nozzle in which the main valve is controlled by a pilot valve and in which no accessory operating fluid or medium is necessary.
It is another object of the instant invention to provide a fire fighting nozzle which is pilot valve controlled, which is simple and rugged in construction, and which is capable of a long life of useful service.
A still further object of the invention is the provision of a fire fighting nozzle making use of a plurality of fire extinguishing media in which each medium is provided with its own actuating button, each button making use of its own medium to control its own main valve.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.